Container and closure lid



Jan. 7, 1969 w. MILLER 3,420,397"

CONTAINER AND CLOSURE LID 'F'iled July 27, 1965 INVENTOIQ BY WILLIAM L.MILLER United States Patent 5 Claims ABSTRACT OF THE DISCLOSURE A thinwalled, thermoformed plastic container having a co-operating closure lidwherein the container is characterized by an inwardly projecting noseextending around the entire periphery adjacent the mouth and the lidincludes a depressed center panel adapted to telescope within thecontainer mouth and a peripheral wall adjoining the panel which has aninwardly depressed circular groove in which the nose is adapted to beseated so as to lock the lid in position when it is telescoped into thecontainer mouth, the nose and groove constituting part of an antinestingfeature for both the container and the lid when a plurality thereof arein stacked relation, and a means incorporated in the nose for ventingthe container when it is used for .a product which may produce excessiveinternal pressure which would otherwise unseat the nose and release thelid.

This invention relates to packaging and is more particularly concernedwith improvements in a container and a closure lid therefor which isespecially adapted for packaging a variety of materials including foodproducts.

Various container and closure lid combinations have been developed forpackaging a variety of products including foodstuffs, with the containerand/or closure lid being formed of thin walled plastic usually of a typewhich may be thermoformed from a web or sheet, employing suitableforming dies. Generally, an effort has been made to incorporate incontainers of this type so-called antinesting features which facilitatethe use of automatic machinery involving the dispensing of thecontainers and/or closure lids from a nested stack thereof. Also,efforts have been made to incorporate in container and lid combinationssome means for venting the container where it is to be used forpack-aging of a food product such as, for example, cottage cheese, whichmay generate a gas after it is enclosed in the package so as to producepressure within the container sufficient to force the closure lid off ifventing is not provided for. Many of these containers and lidcombinations have not been satisfactory for various reasons, and it is ageneral object of the present invention to provide a container and lidcombination especially adapted to be thermoformed from plastic sheetmaterial which is more satisfactory than previous desigins,particularly, in the packaging of foodstuffs,

It is a more specific object of the invention to provide a container anda closure lid therefor, each of which is adapted to be formed fromplastic sheet material so as to coact with each other to provide asanitary, economical and rugged package having a closure member forminga highly satisfactory seal with the container when applied and readilyremovable by the consumer for access to the interior of the container.

It is another object of the invention to provide a container and lidcombination of the type described which is capable of being economicallyproduced by automatic machinery with high volume mass productiontechniques.

It is still another object of the invention to provide a 3,420,397Patented Jan. 7, 1969 container and lid combination wherein thecontainer has an inwardly projecting nose extending around the entireperiphery adjacent the mouth and the lid has a co-operating, inwardlydepressed circular groove in which the nose is adapted to be seated whenthe lid is telescoped into the mouth of the container and wherein thelocking nose and groove constitute part of the antinesting features forboth the container and the lid.

It is a still more specific object of the invention to provide acontainer and lid combination wherein the container comprises a bottomwall and an upstanding side wall which terminates in an outwardlyextending curled rim portion and which has a combination inwardlyprojecting lid locking bead and stacking shoulder adjacent the rimadapted to co-operate with a locking groove in the outer surface of theside wall of the lid when assembled therewith so as to lock the same inclosure forming position within the mouth of the container, and alsoadapted to co-operate with a downwardly facing shoulder below the sameon a like container to provide an antinesting feature when a pluralityof the containers are assembled in stacked relation.

It is another object of the invention to provide a combination containerand closure lid wherein the container has an inwardly directed head ofgenerally V-shaped cross section extending about the periphery thereofadjacent the mouth of the container and the lid has a side wall with aco-operating locking groove in the outer periphery thereof which isspaced above the bottom panel of the lid so as to provide a tight fitwith the container bead and reduce the tendency of the lid to becomeloose when there is upward bulging of the bottom panel as a result ofpressure within the container.

It is another object of the invention to provide a container memberhaving an internal shoulder adjacent the top opening thereof which isadapted to engage in a groove in the external wall of a closure memberso as to form a seal in the vicinity of the groove and the containermember being formed with a venting means incorporated in the shoulderwhich provides a passageway for egress of gaseous fluid withoutresulting in removal of the lid due to a buildup of pressure within thecontainer.

'It is a further, more specific object of the invention to provide anovel closure lid for a plastic container which is configured so as toprovide a sanitary overlay for the lip of the container, which isadapted to nest with other lids without damage, which is molded from onepiece plastic sheet materials, which has a configuration which preventsdamage to the lids even when a stack of nested lids is subject to severecompressive action, which has an easy feed action in a lid dispensingdevice, which has a combination lid retaining and stacking ring forcoaction with the bottom of the next adjacent container when thecontainers assembled with lids are placed in stacked relation and whichis otherwise well adapted for its intended purpose.

These and other objects and advantages of the invention will be apparentfrom a consideration of the container and the lid therefor which isshown by way of illustration in the accompanying drawings wherein:

FIGURE 1 is a side elevation of a container with a closure lid attachedthereto which embodies the principal features of the invention;

FIGURE 2 is a plan view of the container of FIGURE FIGURE 3 is afragmentary cross section taken on the line 3-3 of FIGURE 1, showing theclosure lid applied to the container;

FIGURE 4 is a fragmentary vertical sectional view showing two of thecontainers in stacked relation;

FIGURE 5 is a fragmentary, vertical sectional view showing two of theclosure lids in stacked relation; and

FIGURE 6 is a fragmentary, vertical section similar to FIGURE 3 showinga modified form of the container and closure lid.

Referring first to FIGURES 1 and 2 of the drawings, there is illustrateda package 10 comprising a cup-shaped container 12 and a matching closurelid 14 applied to the mouth of the container. For the purpose ofillustration, the container 12 may be considered as especially designedfor packaging of a food product, for example, cottage cheese.

The container 12 comprises a bottom panel structure 16 (FIGURE 1) ofconventional construction and a side wall 18 which extends upwardly fromthe margins of the bottom panel 16, with an outward taper or slant, andwhich terminates at a mouth defining, outwardly curled rim portion 20(FIGURES 3 and 4). The upper portion or section 22 of the side wall 18immediately below the rim portion 20 is offset outwardly of thelowermost portion 24 thereof and is shaped to provide a peripherallyextending stacking ring structure which incorporates a lid locking beadformation 26 for retaining the closure lid member 14 in the mouth of thecontainer. An outer, downwardly facing stacking shoulder 28 is formed toextend about the periphery of the container at the top edge of the lowerbody portion 24 where it joins the lowermost edge of the outwardlyoffset side wall portion 22. A lower marginal portion 29 of the sidewall section 22 extends upwardly to an inwardly and upwardly tapered orslanted lower or bottom portion 30 of the locking bead formation 26. Thelocking bead formation 26 includes a top shoulder forming portion 32which extends upwardly and outwardly from the junction at 34 with theportion 30 and which terminates at the lower edge of a short wallsection 36, the latter merging into the curled rim portion 20.Preferably, the locking bead formation 26 incorporates inwardly opening,vertical slot formations 40 which constitute passageways for fluid andserve as a venting means when the closure lid 14 is assembled in mouthclosing position on the top of the container 12.

The closure lid member 14 (FIGURES 1, 2, 3 and 5) is formed from asingle sheet of material which is shaped to provide a flat bottom panel42 and a side wall 44 extending upwardly from the margins thereof with arelatively small outward taper, the latter corresponding approximatelyto the taper of the upper wall section 22 of the container so as totelescope within the latter when the lid 14 is assembled with thecontainer 12. The side wall 44 terminates at its upper edge in a top rimportion 46 of downwardly opening, channel-shaped cross section which isadapted to encompass the curled rim portion 20 of the container 12 andform a cap over the same when the lid 14 is assembled in the mouth ofthe container 12. The side wall portion 44 of the closure lid 14 isformed with an outwardly opening, peripheral recess 48 provided by aninwardly extending bead' formation 50 for co-operation with the inwardlyprojecting locking bead formation 26 on the container 12, the beadformation 26 being seated in the recess 48 when the closure lid is inmouth closing position with the side wall portion 44 telescoped withinthe upper side wall portion 22 of the container 12. The recess definingbead formation 50 is spaced above the bottom panel 42 by a side wallsection 52 of appreciable depth or width so that upward flexing of thebottom wall panel 42 due to pressure conditions within the containerwill have a minimum effect on the seal forming contact between the beadformations 26 and 50. The locking bead formation 50 has a crosssectional configuration corresponding approximately to the cross sectionof the locking head 26 with a lower or bottom inwardly and upwardlytapering peripheral ring portion 54 extending above the wall section 52and connecting with an outwardly and upwardly tapered portion 56 formingan upwardly facing shelf which extends to the top wall section 58, theupper portion of which constitutes the inner wall of the rim formation46.

When the closure lid 14 is assembled with the container 12 to close themouth of the latter, the rim section 46 of the closure lid 14 forms acap over the curled rim portion 20 of the container 12 and the lockingbead formation 26 on the container 12 is seated in the recess 48provided by the locking bead formation 50. An effective seal is providedby the contact between the top shoulder portions 32 and 56 and thebottom ring portions 34 and 54 of the co-operating bead formations 26and 50. Any upward flexing of the closure lid bottom panel 42 due toincrease in pressure within the container 12 does not appreciably affectthe seal between the two locking beads 26 and 50 since the resilientwall section 52 is interposed between the panel 42 and the bead 50. Anexcess of pressure within the container due to gas formation in theproduct contained will be relieved or vented through the venting slots40. When the internal pressure in the container reaches a predeterminedamount the top and bottom ends of the slots 40 will open and relieve thepressure before it is sufficient to lift the closure lid and separatethe locking bead formations 26 and 50.

The stacking of the containers 12 is illustrated in FIG- URE 4. Theinternal diameter of the container 12 at the innermost edge of thelocking bead formation 26 is appreciably less than the maximum externaldiameter of the bottom stacking ledge or shoulder 28 so that when onecontainer is positioned in nested relation within another the shoulder28 of the top container rests on the inwardly and downwardly slopingledge 32 of the bead formation 26 of the bottom container so that thecontainer bottom wall portions 24 and the top wall portions 22 arespaced from the corresponding wall portions of the next container in thestack and the bottom container will readily drop away from the nextcontainer in the stack when dispensed from a magazine or the like.

The closure lids 14 are adapted to be stacked for dispensing as shown inFIGURE 5. The diameter of the innermost edge of the locking head 50 isappreciably less than the external diameter of the bottom panel 42 ofthe lid so that the lids may be stacked with the peripheral portion ofthe bottom panel 42 of each lid member resting on the inwardly slopingledge 56 of the locking bead formation 50 on the lid member beneath thesame in the stack so that the wall section 52 is spaced from the wallsection 58 and the members are readily separated for dispensing from thestack.

Referring to FIGURE 6, there is illustrated a modification of thecontainer and lid member. In this form the container 112 has an upperwall portion 122 with a stacking ring structure including a lid lockingbead formation 126 which is modified by forming the bottom portion 130with a rounded contour so that it curves into merging relation with theupper margin of the wall portion 129, the latter defining the lowerportion of the stacking ring structure. The upper shelf forming section132 of the locking bead 126 is slanted downwardly to a somewhat greaterdegree than the shelf section 32. The co-operating bead formation hasthe lower wall section 154 formed on a curve so as to merge into thewall section 152 which separates the same from the bottom panel 142. Thecurvature of the bead sections 130 and 154 is such as to provide goodcontact over a substantial area between the engaging surfaces of thesesections when the lid 114 is telescoped within the mouth of thecontainer 112 and seated in mouth closing position. The inner bottompanel 142 of the closure lid 114 has a relatively narrow marginal ringsection which tapers upwardly and outwardly to the juncture with thevertical wall section 152 and counteracts the tendency of the sealforming contacting surfaces of the wall sections 130 and 154 to separatedue to upward movement of panel 142 resulting from increased pressure inthe container. This panel 160 permits substantial upward movement of thepanel 142 without materially decreasing the contacting areas between thewall sections 130 and 154. The bead formations 126 and 150 both havetheir innermost surfaces rounded and the ledge forming top portions 132and 156 both taper inwardly and downwardly to a somewhat greater degreethan the ledge formations 32 and 56.

The combination lid retaining and stacking ring structure incorporatedin both the container and the closure lid is, in each member, spacedfrom panels or other sections which would tend to reduce the resiliencyin these structures so that the lid will readily snap into mouth closingposition within the container and will not fall out with the developmentof minor pressure in the container which may result from the generationof gas by the contents or from squeezing pressure on the side wall whenthe container is grasped in handling the same. The location of thestacking ring results in more uniformity when the members are fabricatedby thermoforming sheets of a suitable plastic material, such as, forexample, high impact styrene, since the stacking rings are formed in theearly stage of the plastic stretch as the plastic sheet fills theforming mold and before it stretches to minimum thickness.

While specific materials and particular details of construction havebeen referred to in illustrating the preferred forms of the invention,it will be understood that other materials and equivalent structuraldetails may be resorted to within the spirit of the invention.

I claim:

1. A self-venting sanitary package comprising a one piece thin walledplastic container having a bottom wall and an upstanding, outwardlytapering side wall terminating at an outwardly curled lip portiondefining an open end and a one piece snap-on manually removable closureforming lid of thin wall plastic adapted to be inserted within andretained on the open end of said container, said lid having a bottomforming panel and an outwardly tapering side wall upstanding from theperipheral edge of said bottom panel and terminating at an outwardlyextending rim portion which rim portion is shaped to engage over thecurled lip of the container when said lid is assembled in closureforming relation with said container, said container having an inwardlyprojecting shoulder forming bead in the side wall immediately below saidlip portion and said lid having an inwardly depressed groove formed byan inwardly projecting bead in the side wall thereof which is spacedabove said bottom panel and which is adapted to receive said containerbead in snap-in, seal forming relation, said container bead and said lidbead having similar cross sectional configuration so that said containerbead will seat in said groove and provide peripherally extending sealingcontact on at least two vertically spaced surface areas extending inintersecting planes which are inclined relative to the vertical axis ofsaid container.

2. A package as recited in claim 1, and said container bead and said lidbead having cross-sectional configurations which provide sealing contactat two spaced surface engaging areas which are in inwardly convergingplanes extending in a generally diagonal direction upwardly anddownwardly relative to the vertical axis of the package.

3. A closure member for the mouth end of a thin wall plastic containerwhich container is characterized by an outwardly sloping side wallportion at the mouth thereof terminating in an outwardly turned top rimportion and having an inwardly extending peripheral locking bead forco-operation with the closure member which locking head has oppositelyfacing top and bottom surfaces in inwardly converging planes which areinclined relative to the vertical axis of the container, said closuremember being formed of resilient plastic for snap-on engagement over thecontainer rim portion and including a bottom wall forming panel and anupstanding annular wall disposed around the margin of said bottom wallpanel which slants upwardly and outwardly and terminates at a rimportion adapted to encompass the rim portion of the container, saidannular wall having a continuous groove in the outer face thereof whichopens outwardly and which is spaced above the peripheral edge of saidbottom panel and said groove having a configuration correspondinggenerally to the configuration of said bead thereby providing divergingsurfaces which are inclined relative to the vertical axis forfrictionally engaging the opposed top and bottom surfaces of saidcontainer locking bead so as to form a separable double seal therewith.

4. A closure member according to claim 3, and said bottom wall panelhaving a relatively narrow rim section at the peripheral edge thereofwhich is slanted on a relatively small angle upwardly and outwardly to ajuncture with the bottom edge of the annular wall and the externaldiameter at the peripheral edge of said :bottom wall panel being lessthan the internal diameter of the oppositely disposed container wallportion whereby said peripheral edge is normally spaced from saidcontainer wall portion and upward pressure on the bottom Wall panelresulting from predetermined increase in pressure within the containerexpands the annular wall and increases the area in sealing engagementwith the bottom surface of said locking bead.

5. A self-venting sanitary package comprising a one piece containerhaving a bottom wall and upstanding side wall terminating in anoutwardly curled lip portion defining an open end and a one piecesnap-on, manually removable, closure forming lid adapted to be insertedwithin and retained on the open end of said container, which lid has abottom forming panel and upstanding side walls terminating in anoutwardly extending rim portion shaped to encompass the curled lip ofthe container when said lid is assembled in closure forming relationwith said container, said container having an inwardly projecting beadof generally V-shaped cross section and a side wall adjacent said lipportion and said lid having an inwardly depressed, generally V-shaped,outwardly opening groove in the side wall which is spaced above saidbottom panel, and which is adapted to receive the container bead insnap-in seal forming relation, said container bead normally seating insaid groove so that there is seal forming engagement between verticallyspaced top and bottom surfaces of said head and the top and bottomsurfaces defining said groove while the bottom panel is free of sealingengagement with the container wall at the periphery thereof, and saidcontainer bead having circumferentially spaced, axially extendinggrooves which open inwardly of the container and are closed by theinterengaging surfaces when there is minor pressure in the container andwhich are open when there is excessive pressure in the container so asto move the groove forming portions of the lid in a direction toseparate the interengaging top surfaces and unseat the container beadthereby to vent the container so that the movement of the lid portionsis arrested and the lid remains on the container.

References Cited UNITED STATES PATENTS 2,752,972 7/1956 Tupper 220-60 X2,985,354 5/1961 Aldington 229-43 3,055,540 9/1962 Ringlen 229-43 X3,061,139 10/1962 Edwards 220-60 X 3,094,240 6/1963 Wanderer 229-15 X3,112,841 12/1963 Martinelli 229-43 X 3,262,602 7/ 1966 McConnell 220-44X GEORGE E. LOWRANCE, Primary Examiner.

US. Cl. X.R.

